First of all, if they were prescribed by your gp, that's your first mistake. Secondly, a misdiagnosis and treatment has no bearing on their efficacy for those with genuine need. Thirdly, only so many problems can be "handled" before someone becomes suicidal. After years, our hormones can actually be altered and turn what was once a situational problem into a chemical one. Proper medication allows you to establish a baseline and level yourself out.
Have you ever been so depressed that you could not force yourself to get out of bed and function? Have you ever thought that you were a burden and would be doing people a favor by ridding yourself from the world? Have you ever felt so dark that there was no way out? Have you ever held the means of killing yourself in your hands and sat on the brink, too indifferent to even cry about it?
Well, that's where I was when my best friend pretty much drug me into professionals and didn't take no for an answer. I had all of those things you're talking about running through my head, and I felt hopeless. I didn't want the medication. But I had come to the point where I knew what the alternative was. And it didn't work immediately. It took almost two months of medication and counselling before I started to feel a little better. After a year, I was able to start controling my emotions, and consciuosly choosing what to feel. That had never happened in my life. I still had moments of depression, but they were always in passing and never more than a few hours long. And you know what? After two years of having a baseline established, I quit the counselling and I quit the medication. And I've been well ever since. I can't say the drugs were completely responsible, but they were without doubt an integral part of my reestablishment of my sanity and well being. And furthermore, I wouldn't to presume to tell anyone what they should or should not do--that's a medical doctor's job, specifically, a psychiatrist.